Immediately following the Dallas Police shootings, the Fresno Police Department started receiving threats - some have been via social media others phone calls.

Officers across the valley say they are also on alert.

"I took the time to remind our officers to remind them to remain vigilant and back each other up whenever possible," Selma Police Chief Greg Garner said.

At the Fresno City College Police Academy the shooting of a Missouri police officer Friday morning became an unfortunate lesson for cadets learning about traffic stops.

Reports indicate the officer failed to keep an eye on a driver he had just pulled over.

"It is something we will bring up to all cadets as a reminder good officer safety protocol requires you to keep an eye on the person you are contacting," Police Academy director Lt. Richard Lindstrom said.

But officers say ambush-style attacks are difficult to prevent, which is why they believe recent shootings will impact future equipment and training for law enforcement.

"We understand how easily that can occur, especially when our officers respond to thousands of calls a day," Dyer said. "There's an opportunity for people to take advantage of."

But instructors say no matter how much training you have in the classroom some of the most important lessons, like building trust with those they serve can't be taught in cadet school but must be experienced out in the field.

"So when these events it isn't a situation where we have to manufacture a relationship with the community it already exists," Garner said.